Hi guys, so I tried a search but I couldn't find a definitive answer on what to look for while checking the Crankshaft position sensor. A little backstory on the car. 1996 318ti, 160k, automatic. PO said it wouldn't start, tried jumping the starter and it was found to be working. He said he didn't do anything else. I purchased the car after reading some possible causes on this forum, thought it sounded like the crankshaft position sensor. I replaced it blindly, believing it was certainly this sensor, only to have the same result: cranks but no start. Opened the DME connector and it was dry, no corrosion. I checked for spark with an inline tester, no spark while cranking. No sound coming from the fuel pump when key is inserted and turned forward. Brand new battery I just bought a day after I brought the car home. I tested the Crankshaft position sensor that I pulled off the car, on pin 1 and 2, with DVOM set to 2000 ohms, the readout would spike to 1022-750 upon connecting the probes then drop in value to 0. Am I doing this right? Is it supposed to start high then drop rapidly as the probes stay touching the pins? Is this normal and the sensor is still working? Could a brand new one fail right out of the box? Anything else common to look for, moving forward?

So im trying to dig into this car some more and I'm getting more and I cant find the DME unloader relay. It isnt in the compartment behind the battery. And i cant find any other pictures of its location. Ill try and post pictures if anyone can give me a hand.

No spark was detected with an inline spark tester while cranking. Fuel pump is working but does not prime when key is turned. Starter works.

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Why was someone jumping to starter?

Previous owner said he jumped the starter with 12v power to see if it was working. He did not have time or desire to work on the car anymore before I got it The starter does work and turns the engine while cranking with the key.

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When you said "cranking but no spark", was that with the key?

Yes, trying to start with the key.

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Not sure what happens when you put the key in it and try from the description.

It will crank. By cranking, I mean the starter engages and spins the engine. Does not sputter or sound like it wants to start. From what I understand from reading on here, if there was a fault with the key or EWS system, it would not allow the starter to engage.

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The stuff in that cubby will be the DME and the Auto trans unit. There aren't relays in there.

The reason I was checking there, I read that the DME unloader relay was in the DME compartment. But I didn't find anything that looked like a relay or a socket in the wiring harness from the DME

Went out and worked on the car again today. I can jump the fuel pump from the relay socket and fuel pump runs and sends fuel to the rail. It is still not getting spark. Ecm relay socket gets power and the relay is working. It is not sending signal to activate fuel and ignition spark. No codes stored using my OBD2 scanner because i keep disconnecting the battery while i troubleshoot the wiring.

A couple of things to check and ponder: The cranking should trigger the fuel pump. If there is no power to the wire check relays and fuses. Check the FPR coil is getting 12v during cranking. If not the worst problem to cause this fault is a defective ECU. The fact of cranking should trigger the fuel pump. It is not CPS dependant. Holding the relay IN is dependant on the ECU getting CPS pulses. If it turns out you are have no spark and dry plugs then a likely problem is the CPS. Without that input the ECU will not initiate a spark or open the injectors for running. If the plugs are fuel wet but you have no spark then the CPS is good and probably the ECU is ok. Check out the wires, plugs and earth points on the spark system.